CVE-2021-41238 — Vulnerability in Hangfire.Core — CVE Details

Dashboard UI in Hangfire.Core uses authorization filters to protect it from showing sensitive data to unauthorized users. By default when no custom authorization filters specified, `LocalRequestsOnlyAuthorizationFilter` filter is being used to allow only local requests and prohibit all the remote requests to provide sensible, protected by default settings. However due to the recent changes, in version 1.7.25 no authorization filters are used by default, allowing remote requests to succeed. ### Impact Missing authorization when default options are used for the Dashboard UI, e.g. when no custom authorization rules are used as recommended in the [Using Dashboard](https://docs.hangfire.io/en/latest/configuration/using-dashboard.html#configuring-authorization) documentation article. #### Impacted If you are using `UseHangfireDashboard` method with default `DashboardOptions.Authorization` property value, then your installation is impacted: ```csharp app.UseHangfireDashboard(); // Impacted app.UseHangfireDashboard("/hangfire", new DashboardOptions()); // Impacted ``` #### Not Impacted If any other authorization filter is specified in the `DashboardOptions.Authorization` property, the you are not impacted: ```csharp app.UseHangfireDashboard("/hangfire", new DashboardOptions { Authorization = new []{ new SomeAuthorizationFilter(); } // Not impacted }); ``` ### Patches Patch is already available in version [1.7.26](https://github.com/HangfireIO/Hangfire/releases/tag/v1.7.26) and already available on NuGet.org, please see [Hangfire.Core 1.7.26](https://www.nuget.org/packages/Hangfire.Core/1.7.26). Default authorization rules now prohibit remote requests by default again by including the `LocalRequestsOnlyAuthorizationFilter` filter to the default settings. Please upgrade to the newest version in order to mitigate the issue. ### Workarounds It is possible to fix the issue by using the `LocalRequestsOnlyAuthorizationFilter` explicitly when configuring the Dashboard UI. In this case upgrade is not required. ```csharp // using Hangfire.Dashboard; app.UseHangfireDashboard("/hangfire", new DashboardOptions { Authorization = new []{ new LocalRequestsOnlyAuthorizationFilter(); } }); ``` ### References Original GitHub Issue: https://github.com/HangfireIO/Hangfire/issues/1958